Mechanical sand washer



Patented Aug. 23, 1932 WED STATES PATE PAUL KRAMER, OF NORTH HOLLYWOOD,CALIFORNIA MECHANICAL SAND WASHER Application filed J'une e, 1930. seril No. 459,537

This invention relates to mechanical sand washers or machines designedto wash foreign substancefrom sand, and'p'repare it for marketing Inpractice, where large quantities of clean sand are required, it iscustomary to wash the sand by means'of a mechanical arrangement, wherebythe sand is worked through a bath of water, is finally delivered fromthewater as a clean sand product. The type of malchines used for thispurpose consistsof an inclined trough arrangement, leading from thewater bath, with a plurality of drag blades arranged within the troughto reciprocate and draw the sand out of the water and up the inclinedtrough, The objection to this arrangement is the fact that as the 'dragblades pull the sand up the incline, the sand, after leaving the water,is still so thoro-ughly saturated with water that it is in a more orless plastic condition, and as the blades leave the sand to return foranother load, the piles of sand will flow or recede to a great extentdownwardly to its-original position, and, as a result, the efficiency ofthe machine is greatly reduced.

A further objection is raised with respect to the water content of thefinal product. a

With thepresent equipment, the sand delivered at the upper end of theinclined trough contains a high percentage of water. In some cases thisvwet sand is delivered directlyinto trucks which convey it to the job.However, since the sand still contains: so

of time and adding to the cost of transport-ation. In other cases, thesand is deposited from the upper end of; the inclined trough onto aconveyor belt, and then conveyed to storage bins where it is allowed todrain.

The plastic condition of the saturated sand again raises a seriousobjection, in that excessively broad belts must be used in order to muchwater, it drains from the truck and accommodate the spreading of thesand,'and

even then it willrun off the edge of thebelt and into the bearings forthe rollers. Furthermore, in arrangements of this type, provision mustbe made to handle the drainage water after the sand is stored in orderthat trucks may approach the bins for a load. Perceiving that theseobjections could besubstantially eliminated, andthe output o-fthemachine increased I conceived'the idea of draining the sand before itleft the machine by providing water drains in the drag blades whichwould permit the water to compress from the sand and pass through theblades on the upstroke. This operates effectively and efliciently toproduce a drier sandproduct on each: successive stroke, since the-sand,

while being forced'up the incline, is in an ideal state for dewatering.This result isia final product of comparatively dry sand.

Accordingly, it becomes an objeot ofthis in-.

- vention to provide drag blades in mechanical sand washers of thecharacter described with perforations either in the nature of 'holesorscreening in the body of the'blade to drain water during the operationofdragging the sand up the inclined trough.

A noteworthy feature of my invention consists in countersinkingthehol'es on the-side of the blade opposite the sand. This results inproducing openings through the 1 blades that are free from clogging,and-remain substantially self-cleaning. Accordingly, it'be- 7 comes amore specific object of this invention to provide drag blades havingcountersunk holes therethrough. j

- Other objects and advantages .will become apparent as thedescriptionproceeds in conjunction with the drawing in which 7 Fig.1 is a sectionalview showing my'inventionalmech anical sand washer the drag bladesshowingimore' clearly my invention;

; Referring to the-drawing, and particularly Fig. 2 is an enlargedfragmentary view of oo vention embodied in combination with a con Fig. 3is a section taken on line 33 of Fig.

to Fig. 1, I have illustrated a conventional sand washing machine. Such.a machine usually comprises a water tank A for washing the sand, aninclined trough B oined to the water tank in a manner to receive thesand from the waterv tank and a drag blade arrangement generallydesignated C. The drag blade arrangeinent is mounted upon superstructure11 by means of links 12 and bell cranks 13. Means is provided forreciprocating the drag blade arrangement G within the trough B to dragsand from the water tank A up theinclined trough, such means consistingof a double eccentric shown at 14:, and, having connected therewith apair of connecting rods 15 andl6. The connecting rod 15 is arrangedtolift the dragiblades on the return stroke by moansof the bell cranks 13and the links 12,

and therodlG is arranged to'reciprocate' the drag blade arrangement, thetwo -1no vements being so synchronized that the drag blades will operatetodiaw sand up. the incline and will return in an elevated positionformanother load of sand. The sand, consequently,

.is left in smallp-iles onthebottom of the in- .elined trough. lVhenthesand is worked up Inclined trough B: .to the point. 17,.it is droppedeither into a truck, a conveyor systern, or a storage bin- .cifioal-ly'describing this embodimentof: my in- :vention; it is? observed that thedrag blade arrangcmont is equipped with a pair of channel irons, shownat 18'and 19; Attached to the members .18. and '19 are a plurality ofdrag -=bla.des-- designated 20; The nieansof attachhig-theblades 20 ccthe-"channel irons: 18-.a.nd 19 consists. of a member 21, which, inthis-instance, is a piece-of angle iron bent at right angles. to folin-22 and 23. The; leg .22 is attachedto thelower side of the channel 18'by 'means of a bolt 24, and the leg QSisutilized for mountlng the blade20 by means ofbolts 25. A brace member QG-extendsfrom the lmvcrbolt25to=the loweredgc of the channel ironldandisattaehed thereto bymeans of a bolt 27. It is to bev understood thatthesame structure isutilized in connection with the channel iron.19.- This strt-tcturewillbe recognized-asproviding a rigid mounting for-the a blades20'. Asbefore stated, the purposeof this mventionais to provide in theblades'QOa .means of dewateni-ng the sand? as itis dragged up the incline. 1 Thepreferred means is shown in Figs. 2 and3, and consists of holes 28wthroughthe'hody of the plate.

In Fig. 4;, I have shown another formwhich consistsofincorporating ascreen 29. for the main body of the blade.

. In practice, I have found that holes of'uni- 7 form bore have atendency to clogan-d reduce theefficiency of my invention Accond-in-gly,

the sand up the inclined trough B, the sand accumulates in front of theblade somewhat as shownat 30. It is understood that as the sandleavesthe tank A, it is thoroughly saturated with water, and that unless thewater is given an o portunity to drain out of the sand, thesan w-ill'bein such a plastic condition that as the blade leaves the sand in aseries of piles in the trough and returns on its downwardstroke, thesand, due to gravity,

will flow downwardly with the blade and the etficiency of the machinewill be greatly reduced. WVith my invention, alargepercentage ofthewaterin the sand in front of the blade is allowed to compress out of thesand and pass. through the holes 28, whereupon it 35 flowsdownwardlyover: the back of the blade" and will flow down thetroughunder the piles of sand and back into the tank A. The re- Thefinal'product is delivered over the end 17 of. the trough B in a.comparativelydry state. Not only this benefitachieved, but also is.eachpile of sand successively dewateredand. 5

left. in a drier condition, whereby it will-bet vter maintainitsposition as the blade'leaves it. for the return stroke. This clearlyincreases the efficiency of the machine, since the blade-on thevupstrokeis enabledto pick up a oo greater load ofsand.

The. foregoing advantages will be recognized asa result of my invention.

Although I have shown drag blades equipped with holes and with screens,never-.

is intended to include drag blades. of the na- 116 true described havingopenings therethrough adapted to pass water.

I claim as my invention: In a mechanlcal sand washer havmg an 111-clined trough with drag blades adapted to drag sand upthe trough: meansassociated with said blades for dewatering the sand'as it is forced upthe inclined trough, said means embodying holes through said bladesadapted to pass water and restrain sand, said .holesbeing countersunk onthe side opposite

